package store

import (
	"errors"
	"strings"
	"testing"
	"time"

	"github.com/mattn/go-sqlite3"

	"lbryio/lbry-id/auth"
)

func expectAccountMatch(
	t *testing.T,
	s *Store,
	normEmail auth.NormalizedEmail,
	expectedEmail auth.Email,
	password auth.Password,
	seed auth.ClientSaltSeed,
	expectedVerifyTokenString auth.VerifyTokenString,
	approxVerifyExpiration *time.Time,
) {
	var key auth.KDFKey
	var salt auth.ServerSalt
	var email auth.Email
	var verifyExpiration *time.Time
	var verifyTokenString auth.VerifyTokenString

	err := s.db.QueryRow(
		`SELECT key, server_salt, email, verify_token, verify_expiration from accounts WHERE normalized_email=? AND client_salt_seed=?`,
		normEmail, seed,
	).Scan(&key, &salt, &email, &verifyTokenString, &verifyExpiration)
	if err != nil {
		t.Fatalf("Error finding account for: %s %s - %+v", normEmail, password, err)
	}

	match, err := password.Check(key, salt)
	if err != nil {
		t.Fatalf("Error checking password for: %s %s - %+v", email, password, err)
	}
	if !match {
		t.Fatalf("Password incorrect for: %s %s", email, password)
	}

	if email != expectedEmail {
		t.Fatalf("Email case not as expected. Want: %s Got: %s", email, expectedEmail)
	}

	if verifyTokenString != expectedVerifyTokenString {
		t.Fatalf(
			"Verify token string not as expected. Want: %s Got: %s",
			verifyTokenString,
			expectedVerifyTokenString,
		)
	}

	if approxVerifyExpiration != nil {
		if verifyExpiration == nil {
			t.Fatalf("Expected verify expiration to not be nil")
		}
		expDiff := approxVerifyExpiration.Sub(*verifyExpiration)
		if time.Second < expDiff || expDiff < -time.Second {
			t.Fatalf(
				"Verify expiration not as expected. Want approximately: %s Got: %s",
				verifyExpiration,
				approxVerifyExpiration,
			)
		}
	}
	if approxVerifyExpiration == nil && verifyExpiration != nil {
		t.Fatalf("Expected verify expiration to be nil. Got: %+v", verifyExpiration)
	}
}

func expectAccountNotExists(t *testing.T, s *Store, normEmail auth.NormalizedEmail) {
	rows, err := s.db.Query(
		`SELECT 1 from accounts WHERE normalized_email=?`,
		normEmail,
	)
	if err != nil {
		t.Fatalf("Error finding account for: %s - %+v", normEmail, err)
	}
	defer rows.Close()

	for rows.Next() {
		t.Fatalf("Expected no account for: %s", normEmail)
	}

	// found nothing, we're good
}

// Test CreateAccount
// Try CreateAccount twice with the same email and different password, error the second time
func TestStoreCreateAccount(t *testing.T) {
	s, sqliteTmpFile := StoreTestInit(t)
	defer StoreTestCleanup(sqliteTmpFile)

	email, normEmail := auth.Email("Abc@Example.Com"), auth.NormalizedEmail("abc@example.com")
	password, seed := auth.Password("123"), auth.ClientSaltSeed("abcd1234abcd1234")

	// Get an account, come back empty
	expectAccountNotExists(t, &s, normEmail)

	// Create an account. Make it verified (i.e. no token) for the usual
	// case. We'll test unverified (with token) separately.
	if err := s.CreateAccount(email, password, seed, ""); err != nil {
		t.Fatalf("Unexpected error in CreateAccount: %+v", err)
	}

	// Get and confirm the account we just put in
	expectAccountMatch(t, &s, normEmail, email, password, seed, "", nil)

	newPassword := auth.Password("xyz")

	// Try to create a new account with the same email and different password,
	// fail because email already exists
	if err := s.CreateAccount(email, newPassword, seed, ""); err != ErrDuplicateAccount {
		t.Fatalf(`CreateAccount err: wanted "%+v", got "%+v"`, ErrDuplicateAccount, err)
	}

	differentCaseEmail := auth.Email("aBC@examplE.CoM")

	// Try to create a new account with the same email different capitalization.
	// fail because email already exists
	if err := s.CreateAccount(differentCaseEmail, password, seed, ""); err != ErrDuplicateAccount {
		t.Fatalf(`CreateAccount err (for case insensitivity check): wanted "%+v", got "%+v"`, ErrDuplicateAccount, err)
	}

	// Get the email and same *first* password we successfully put in
	expectAccountMatch(t, &s, normEmail, email, password, seed, "", nil)
}

// Try CreateAccount with a verification string, thus unverified
func TestStoreCreateAccountUnverified(t *testing.T) {
	s, sqliteTmpFile := StoreTestInit(t)
	defer StoreTestCleanup(sqliteTmpFile)

	email, normEmail := auth.Email("Abc@Example.Com"), auth.NormalizedEmail("abc@example.com")
	password, seed := auth.Password("123"), auth.ClientSaltSeed("abcd1234abcd1234")

	// Create an account
	if err := s.CreateAccount(email, password, seed, "abcd1234abcd1234abcd1234abcd1234"); err != nil {
		t.Fatalf("Unexpected error in CreateAccount: %+v", err)
	}

	// Get and confirm the account we just put in
	approxVerifyExpiration := time.Now().Add(time.Hour * 24 * 2).UTC()
	expectAccountMatch(t, &s, normEmail, email, password, seed, "abcd1234abcd1234abcd1234abcd1234", &approxVerifyExpiration)
}

// Test GetUserId for nonexisting email
func TestStoreGetUserIdAccountNotExists(t *testing.T) {
	s, sqliteTmpFile := StoreTestInit(t)
	defer StoreTestCleanup(sqliteTmpFile)

	email, password := auth.Email("abc@example.com"), auth.Password("123")

	// Check that there's no user id for email and password first
	if userId, err := s.GetUserId(email, password); err != ErrWrongCredentials || userId != 0 {
		t.Fatalf(`GetUserId error for nonexistant account: wanted "%+v", got "%+v. userId: %v"`, ErrWrongCredentials, err, userId)
	}
}

// Test GetUserId for existing account, with the correct and incorrect password
func TestStoreGetUserIdAccountExists(t *testing.T) {
	s, sqliteTmpFile := StoreTestInit(t)
	defer StoreTestCleanup(sqliteTmpFile)

	createdUserId, email, password, _ := makeTestUser(t, &s)

	// Check that the userId is correct for the email, irrespective of the case of
	// the characters in the email.
	lowerEmail := auth.Email(strings.ToLower(string(email)))
	upperEmail := auth.Email(strings.ToUpper(string(email)))

	// Check that there's now a user id for the email and password
	if userId, err := s.GetUserId(lowerEmail, password); err != nil || userId != createdUserId {
		t.Fatalf("Unexpected error in GetUserId: err: %+v userId: %v", err, userId)
	}

	// Check that there's now a user id for the email and password
	if userId, err := s.GetUserId(upperEmail, password); err != nil || userId != createdUserId {
		t.Fatalf("Unexpected error in GetUserId: err: %+v userId: %v", err, userId)
	}

	// Check that it won't return if the wrong password is given
	if userId, err := s.GetUserId(email, password+auth.Password("_wrong")); err != ErrWrongCredentials || userId != 0 {
		t.Fatalf(`GetUserId error for wrong password: wanted "%+v", got "%+v. userId: %v"`, ErrWrongCredentials, err, userId)
	}
}

func TestStoreAccountEmptyFields(t *testing.T) {
	// Make sure expiration doesn't get set if sanitization fails
	tt := []struct {
		name           string
		email          auth.Email
		clientSaltSeed auth.ClientSaltSeed
		password       auth.Password
	}{
		{
			name:           "missing email",
			email:          "",
			clientSaltSeed: "abcd1234abcd1234",
			password:       "xyz",
		},
		{
			name:           "missing client salt seed",
			email:          "a@example.com",
			clientSaltSeed: "",
			password:       "xyz",
		},
		// Not testing empty key and salt because they get generated to something
		// non-empty in the method, even if email is empty
	}

	for _, tc := range tt {
		t.Run(tc.name, func(t *testing.T) {
			s, sqliteTmpFile := StoreTestInit(t)
			defer StoreTestCleanup(sqliteTmpFile)

			var sqliteErr sqlite3.Error

			err := s.CreateAccount(tc.email, tc.password, tc.clientSaltSeed, "")
			if errors.As(err, &sqliteErr) {
				if errors.Is(sqliteErr.ExtendedCode, sqlite3.ErrConstraintCheck) {
					return // We got the error we expected
				}
			}
			t.Errorf("Expected check constraint error for empty field. Got %+v", err)
		})
	}
}

// Test GetClientSaltSeed for existing account
func TestStoreGetClientSaltSeedAccountSuccess(t *testing.T) {
	s, sqliteTmpFile := StoreTestInit(t)
	defer StoreTestCleanup(sqliteTmpFile)

	_, email, _, createdSeed := makeTestUser(t, &s)

	// Check that the seed is correct for the email, irrespective of the case of
	// the characters in the email.
	lowerEmail := auth.Email(strings.ToLower(string(email)))
	upperEmail := auth.Email(strings.ToUpper(string(email)))

	if seed, err := s.GetClientSaltSeed(lowerEmail); err != nil || seed != createdSeed {
		t.Fatalf("Unexpected error in GetClientSaltSeed: err: %+v seed: %v", err, seed)
	}
	if seed, err := s.GetClientSaltSeed(upperEmail); err != nil || seed != createdSeed {
		t.Fatalf("Unexpected error in GetClientSaltSeed: err: %+v seed: %v", err, seed)
	}
}

// Test GetClientSaltSeed for nonexisting email
func TestStoreGetClientSaltSeedAccountNotExists(t *testing.T) {
	s, sqliteTmpFile := StoreTestInit(t)
	defer StoreTestCleanup(sqliteTmpFile)

	email := auth.Email("abc@example.com")

	// Check that there's no user id for email and password first
	if seed, err := s.GetClientSaltSeed(email); err != ErrWrongCredentials || seed != "" {
		t.Fatalf(`GetClientSaltSeed error for nonexistant account: wanted "%+v", got "%+v. seed: %v"`, ErrWrongCredentials, err, seed)
	}
}